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Marc A. Adams, Sherry Ryan, Jacqueline Kerr, James F. Sallis, Kevin Patrick, Lawrence D. Frank and Gregory J. Norman

Background:

Concurrent validity of Neighborhood Environment Walkability Scale (NEWS) items was evaluated with objective measures of the built environment using geographic information systems (GIS).

Methods:

A sample of 878 parents of children 10 to 16 years old (mean age 43.5 years, SD = 6.8, 34.8% non-White, 63.8% overweight) completed NEWS and the International Physical Activity Questionnaire. GIS was used to develop 1-mile street network buffers around participants’ residences. GIS measures of the built environment within participants’ buffers included percent of commercial and institutional land uses; number of schools and colleges, recreational facilities, parks, transit stops, and trees; land topography; and traffic congestion.

Results:

Except for trees and traffic, concordance between the NEWS and GIS measures were significant, with weak to moderate effect sizes (r = −0.09 to −0.36, all P ≤ 01). After participants were stratified by physical activity level, stronger concordance was observed among active participants for some measures. A sensitivity analysis of self-reported distance to 15 neighborhood destinations found a 20-minute (compared with 10- or 30-minute) walking threshold generally had the strongest correlations with GIS measures.

Conclusions:

These findings provide evidence of the concurrent validity of self-reported built environment items with objective measures. Physically active adults may be more knowledgeable about their neighborhood characteristics.

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Pedro Rodrigues, Trampas TenBroek and Joseph Hamill

“Excessive” pronation is often implicated as a risk factor for anterior knee pain (AKP). The amount deemed excessive is typically calculated using the means and standard deviations reported in the literature. However, when using this method, few studies find an association between pronation and AKP. An alternative method of defining excessive pronation is to use the joints’ available range of motion (ROM). The purposes of this study were to (1) evaluate pronation in the context of the joints’ ROM and (2) compare this method to traditional pronation variables in healthy and injured runners. Thirty-six runners (19 healthy, 17 AKP) had their passive pronation ROM measured using a custom-built device and a motion capture system. Dynamic pronation angles during running were captured and compared with the available ROM. In addition, traditional pronation variables were evaluated. No significant differences in traditional pronation variables were noted between healthy and injured runners. In contrast, injured runners used significantly more of their available ROM, maintaining a 4.21° eversion buffer, whereas healthy runners maintained a 7.25° buffer (P = .03, ES = 0.77). Defining excessive pronation in the context of the joints’ available ROM may be a better method of defining excessive pronation and distinguishing those at risk for injury.

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Hairul A. Hashim, Golok Freddy and Ali Rosmatunisah

Background:

The current study was undertaken to examine the associations between self-determination, exercise habit, anxiety, depression, stress, and academic achievement among adolescents aged 13 and 14 years in eastern Malaysia.

Methods:

The sample consisted of 750 secondary school students (mean age = 13.4 years, SD = 0.49). Participants completed self-report measures of exercise behavioral regulation, negative affect, and exercise habit strength. Midyear exam results were used as an indicator of academic performance. Structural equation modeling was used to analyze the data.

Results:

The results of structural equation modeling revealed a close model fit for the hypothesized model, which indicates that higher levels of self-determination were positively associated with habituated exercise behavior. In turn, exercise habit strength fostered academic achievement and buffered the debilitative effect of stress, depression, and anxiety on student academic performance. The analysis of model invariance revealed a nonsignificant difference between male and female subjects.

Conclusion:

The findings support the notion that habituated exercise fosters academic performance. In addition, we found that habituated exercise buffers the combined effects of stress, anxiety and depression on academic performance. The finding also supports the roles of self-determination in promoting exercise habituation.

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Megan Brannan, Trent A. Petrie, Christy Greenleaf, Justine Reel and Jennifer Carter

In this study, we extended past research (Brannan & Petrie, 2008; Tylka, 2004) by examining perfectionism, optimism, self-esteem, and reasons for exercising as moderators of the body dissatisfaction-bulimic symptoms relationship among female collegiate athletes (N= 204). Hierarchical moderated regression was used to control for social desirability and physical size and then tested the main and interactive effects of the models. Body dissatisfaction was related to the measure of bulimic symptoms, accounting for 24% of the variance. Four variables were statistically significant as moderators. More concern over mistakes and being motivated to exercise to improve appearance and attractiveness or to socialize and improve mood increased the strength of the relationship between body dissatisfaction and bulimic symptoms. Self-esteem had a buffering effect that resulted in a weakened relationship.

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Thomas D. Fahey, James D. Larsen, George A. Brooks, William Colvin, Steven Henderson and Darrel Lary

Five trained, fasted male cyclists rode a cycle ergometer three times at 50% of VO2,max for 180 min. Using a balanced order, double-blind procedure,subjects were given either a solution containing polylactate (PL: 80% polylactate, 20% sodium lactate, in 7% solution with water), glucose polymer (GP: multidextrin in 7% solution with water), or control (C: water sweetened with aspartame) 5 min before exercise and at 20-min intervals during exercise. Venous blood samples were taken at rest and at 20-min intervals during exercise. In general, PL and GP rendered similar results except that pH and bicarbonate (HCO3) were higher in PL. There were no differences between treatments in perceived exertion, sodium, potassium, chloride, lactate, heart rate, oxygen consumption, rectal temperature, or selected skin temperatures. These data show that polylactate may help maintain blood glucose and enhance blood buffering capacity during prolonged exercise and could be a useful component in an athletic fluid replacement beverage.

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Russell Jago, Tom Baranowski and Michael Harris

Background:

It is not clear if relationships between GIS obtained environmental features and physical activity differ according to the method used to code GIS data.

Methods:

Physical activity levels of 210 Boy Scouts were measured by accelerometer. Numbers of parks, trails, gymnasia, bus stops, grocery stores, and restaurants within the commonly used 400 m and 1-mile (1609.3 m) buffers of subject residences and distance to the nearest feature were calculated. Residential density, connectivity, and crime rate were calculated. Regression models with minutes of sedentary, light, or moderate-to-vigorous activity as dependent variables and environmental and demographics as independent variables were run with backward deletion of environmental variables.

Results:

Park, crime, and gym variables were associated with physical activity, but relationships varied according to whether a 400 m, 1 mile, or nearest criteria was used.

Conclusion:

Environmental variables were associated with the physical activity of adolescent males, but the association was method dependent.

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Gregory J. Norman, Sandra K. Nutter, Sherry Ryan, James F. Sallis, Karen J. Calfas and Kevin Patrick

Background:

Neighborhood-level environmental features have been associated with adult physical activity and weight status, but this link has not been established for adolescents.

Methods:

Community design and access to recreational facilities variables were derived using geographic information systems (GIS) for 799 adolescents (age 11 to 15 y, mean = 12.8 y, 53% girls, 43% ethnic minority). Environment variables were calculated for a 1-mile buffer around each participant’s residence. Accelerometers measured min/d of physical activity.

Results:

Number of nearby recreation facilities and number of nearby parks correlated positively with girls’ physical activity, and intersection density inversely related to girls’ physical activity. Retail floor area ratio correlated positively with boys’ physical activity. No community design or access to recreation variables were related to BMI-percentile.

Conclusions:

There was limited evidence that both community design and access to recreation facilities variables were associated with adolescent physical activity, but additional built environment variables need to be studied that have particular relevance for youth.

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Steven L. Proctor and Candace Boan-Lenzo

This study examined the athletic status differences in reported depressive symptoms between male intercollegiate team sport athletes (n= 66) and male nonathletes (n = 51) enrolled at one of two public universities in the Southeastern United States, while controlling for preferred (task-oriented and emotion-oriented) coping strategies. Analysis of covariance (ANCOVA) revealed that the athletes reported significantly fewer depressive symptoms than nonathletes while controlling for coping strategy selection (p< .05). In terms of the actual prevalence rates of depressive symptoms, 29.4% of the nonathletes met the criterion for possible depression compared with only 15.6% of the athletes. Overall, athletic participation in an intercollegiate team sport appears related to lower levels of depression. The potentially distress-buffering aspects of athletic involvement and implications for future research are discussed.

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Tracie J. Rogers and Daniel M. Landers

The mediating effect of peripheral narrowing in the negative life event stress (N-LES)/athletic injury relationship was investigated. LES and other psychosocial variables were measured, and peripheral vision was assessed in nonstressful (practice day) and stressful (game day) sport situations. Results showed that total LES, N-LES, and psychological coping skills significantly contributed to the prediction of the occurrence of athletic injury. Additionally, psychological coping skills buffered the N-LES/athletic injury relationship. Peripheral narrowing during stress significantly mediated 8.1% of the N-LES/athletic injury relationship. The findings support the predictions of the model of stress and injury, provide evidence for peripheral narrowing as a mechanism in the LES/athletic injury relationship, and suggest directions for future research examining mediating effects in the model of stress and injury.

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Sarah E. Martiny, Ilka H. Gleibs, Elizabeth J. Parks-Stamm, Torsten Martiny-Huenger, Laura Froehlich, Anna-Lena Harter and Jenny Roth

Based on research on stereotype threat and multiple identities, this work explores the beneficial effects of activating a positive social identity when a negative identity is salient on women’s performance in sports. Further, in line with research on the effects of anxiety in sports, we investigate whether the activation of a positive social identity buffers performance from cognitive anxiety associated with a negative stereotype. Two experiments tested these predictions in field settings. Experiment 1 (N = 83) shows that the simultaneous activation of a positive (i.e., member of a soccer team) and a negative social identity (i.e., woman) led to better performance than the activation of only a negative social identity for female soccer players. Experiment 2 (N = 46) demonstrates that identity condition moderated the effect of cognitive anxiety on performance for female basketball players. Results are discussed concerning multiple identities’ potential for dealing with stressful situations.